Add test coverage for the repeat nodes

node-graph/nodes/repeat/Cargo.toml

@@ -24,9 +24,3 @@ log = { workspace = true }
 
 # Optional workspace dependencies
 serde = { workspace = true, optional = true }
-
-[dev-dependencies]
-graphene-core = { workspace = true }
-vector-nodes = { workspace = true }
-tokio = { workspace = true, features = ["macros", "rt"] }
-kurbo = { workspace = true }

node-graph/nodes/repeat/src/repeat_nodes.rs

@@ -179,3 +179,145 @@ fn repeat_on_points<T: Into<Graphic> + Default + Send + Clone + 'static>(
 
 	Ok(result_list)
 }
+
+#[cfg(test)]
+mod test {
+	use super::*;
+	use core_types::arena::Arena;
+	use core_types::context::{ContextImpl, EvalScope, ExtractIndex, ExtractPosition};
+	use core_types::gpoll::GPoll;
+	use core_types::list::Item;
+	use core_types::node::{LazyInput, Node, StatusCell};
+	use vector_types::subpath::Subpath;
+
+	const TEST_POSITION: &str = "test-position";
+
+	struct ValueNode<T>(T);
+
+	impl<T: Clone, Input> Node<Input> for ValueNode<T> {
+		type Output = T;
+
+		fn eval(&self, _input: &Input) -> GPoll<T> {
+			GPoll::Final(self.0.clone())
+		}
+	}
+
+	/// Returns one default `Vector` whose transform records the innermost context index in its x translation.
+	struct IndexProbe;
+
+	impl<Input: ExtractIndex> Node<Input> for IndexProbe {
+		type Output = List<Vector>;
+
+		fn eval(&self, input: &Input) -> GPoll<List<Vector>> {
+			let index = input.try_index().and_then(|mut levels| levels.next()).expect("repeat must push an index level");
+			let mut list = List::new();
+			list.push(Item::new_from_element(Vector::default()).with_attribute(ATTR_TRANSFORM, DAffine2::from_translation(DVec2::new(index as f64, 0.))));
+			GPoll::Final(list)
+		}
+	}
+
+	/// Returns one default `Vector` recording the innermost context position under `TEST_POSITION`.
+	struct PositionProbe;
+
+	impl<Input: ExtractPosition> Node<Input> for PositionProbe {
+		type Output = List<Vector>;
+
+		fn eval(&self, input: &Input) -> GPoll<List<Vector>> {
+			let position = input.try_position().and_then(|mut positions| positions.next()).expect("repeat_on_points must push a position level");
+			let mut list = List::new();
+			list.push(Item::new_from_element(Vector::default()).with_attribute(TEST_POSITION, DAffine2::from_translation(position)));
+			GPoll::Final(list)
+		}
+	}
+
+	fn single_default_vector() -> List<Vector> {
+		List::new_from_element(Vector::default())
+	}
+
+	fn row_translations(list: &List<Vector>, key: &str) -> Vec<DVec2> {
+		(0..list.len()).map(|index| list.attribute_cloned_or_default::<DAffine2>(key, index).translation).collect()
+	}
+
+	macro_rules! test_ctx {
+		($ctx:ident, $cell:ident) => {
+			let arena = Arena::new(4096).unwrap();
+			let generations = [];
+			let scope = EvalScope::new(None, None, None, &generations, &arena);
+			let $ctx = ContextImpl::root(&scope);
+			let $cell = StatusCell::default();
+		};
+	}
+
+	#[test]
+	fn repeat_pushes_the_iteration_index_in_order() {
+		test_ctx!(ctx, cell);
+
+		let x_translations = |values: [f64; 3]| values.map(|x| DVec2::new(x, 0.)).to_vec();
+
+		let forward = super::repeat(&ctx, LazyInput::new(&IndexProbe, &cell, 0), 3, false).unwrap();
+		assert_eq!(row_translations(&forward, ATTR_TRANSFORM), x_translations([0., 1., 2.]));
+
+		let reversed = super::repeat(&ctx, LazyInput::new(&IndexProbe, &cell, 0), 3, true).unwrap();
+		assert_eq!(row_translations(&reversed, ATTR_TRANSFORM), x_translations([2., 1., 0.]));
+	}
+
+	#[test]
+	fn repeat_array_spaces_copies_along_the_direction() {
+		test_ctx!(ctx, cell);
+		let direction = DVec2::new(1.5, 0.);
+		let count = 3;
+
+		let content = ValueNode(single_default_vector());
+		let repeated = super::repeat_array(&ctx, LazyInput::new(&content, &cell, 0), direction, 0., count).unwrap();
+
+		assert_eq!(repeated.len(), count as usize);
+		for (index, translation) in row_translations(&repeated, ATTR_TRANSFORM).into_iter().enumerate() {
+			let expected = index as f64 * direction / (count - 1) as f64;
+			assert!(translation.abs_diff_eq(expected, 1e-10), "copy {index}: {translation:?} != {expected:?}");
+		}
+	}
+
+	#[test]
+	fn repeat_array_single_copy_stays_finite() {
+		test_ctx!(ctx, cell);
+
+		let content = ValueNode(single_default_vector());
+		let repeated = super::repeat_array(&ctx, LazyInput::new(&content, &cell, 0), DVec2::new(12., 10.), 45., 1).unwrap();
+
+		assert_eq!(repeated.len(), 1);
+		let transform: DAffine2 = repeated.attribute_cloned_or_default(ATTR_TRANSFORM, 0);
+		assert!(transform.abs_diff_eq(DAffine2::IDENTITY, 1e-10), "single copy must not divide by zero: {transform:?}");
+	}
+
+	#[test]
+	fn repeat_radial_rotates_copies_around_the_center() {
+		test_ctx!(ctx, cell);
+		let (radius, count) = (5., 4);
+
+		let content = ValueNode(single_default_vector());
+		let repeated = super::repeat_radial(&ctx, LazyInput::new(&content, &cell, 0), 0., radius, count).unwrap();
+
+		assert_eq!(repeated.len(), count as usize);
+		for index in 0..count as usize {
+			let transform: DAffine2 = repeated.attribute_cloned_or_default(ATTR_TRANSFORM, index);
+			let expected = DAffine2::from_angle((TAU / count as f64) * index as f64) * DAffine2::from_translation(radius * DVec2::Y);
+			assert!(transform.abs_diff_eq(expected, 1e-10), "copy {index}: {transform:?} != {expected:?}");
+		}
+	}
+
+	#[test]
+	fn repeat_on_points_pushes_each_point_as_the_position() {
+		test_ctx!(ctx, cell);
+		let positions = [DVec2::new(40., 20.), DVec2::ONE, DVec2::new(-42., 9.), DVec2::new(10., 345.)];
+		let points = List::new_from_element(Vector::from_subpath(Subpath::from_anchors(positions, false)));
+
+		let generated = super::repeat_on_points(&ctx, points.clone(), LazyInput::new(&PositionProbe, &cell, 0), false).unwrap();
+		assert_eq!(row_translations(&generated, ATTR_TRANSFORM), positions.to_vec());
+		assert_eq!(row_translations(&generated, TEST_POSITION), positions.to_vec());
+
+		let reversed = super::repeat_on_points(&ctx, points, LazyInput::new(&PositionProbe, &cell, 0), true).unwrap();
+		let mut expected = positions.to_vec();
+		expected.reverse();
+		assert_eq!(row_translations(&reversed, ATTR_TRANSFORM), expected);
+	}
+}